The Rays optioned Hu to Triple-A Durham on Wednesday, Marc Topkin of the Tampa Bay Times reports.
A corresponding transaction hasn't been announced, but it's expected that Hu's spot on the active roster will be filled by Jonny Venters (hamstring), who is on track to return from the 10-day disabled list. Hu's latest stint with the Rays lasted just two days, with the right-hander making a relief appearance in Tuesday's 4-0 loss. He gave up a run on two hits and struck out four over 2.1 innings in the outing.